The present invention relates to a novel and useful clutch mechanism adapted to selectively engage two rotating, power transmitting members. More specifically, the resilient gear coupling clutch assembly of the instant invention is intended to selectively synchronize and positively engage the rotating input and output shafts as might be incorporated into a motor vehicle transmission.
As more powerful engines and more rugged transmissions are built to match the increasing weight and payload of motor vehicles, complementary improvements in clutch structure and function have been sought. Furthermore, the increasing concern about efficiency and fuel conservation has added a new parameter to the design-efficiency equation.
Conventional motor vehicle friction clutch assemblies commonly utilize what is known in the art as a disc pack clutch assembly. The disc pack comprises a plurality of interleaved discs. One alternate set of discs is attached to an input or drive member and the second alternate set of discs is attached to an output or driven member. Compression of this disc pack by hydraulic or electric means increases the friction between the discs, synchronizes the speed of the input and output members and transmits power therebetween.
As it becomes necessary to transmit increasingly large amounts of power through the disc pack, two problems arise. The first is a limitation on size. Either larger plates, more plates, or more and larger plates are required to transfer more power. The clutch assembly may therefore become so bulky that it will not fit conveniently into the space allocated for it in the motor vehicle. The second problem is a product of the increased size. By increasing disc pack surface area, the disengaged friction between the input and output members is also increased. This means more power must be delivered by the engine at operating speeds in a multiple speed transmission, and the result is increased fuel consumption. The alternative to a large clutch is often a smaller clutch or a clutch with fewer disc packs operated at or near the limit of its power handling capacity. This creates problems of a more conventional nature. It will slip under high load conditions with premature failure due to overheating of the clutch assembly.